Ignition apparatus



May 20, 1930.

W. A. CHRYST IGNITION APPARATUS Filed Aug. 5, 1927 Patented Ma go; 19 30UNITED \STATES PATENT OFFICE wnzLrA'n A. CHBYST, or nAx'ron, OHIO,ASSIGNOR .ro DELCO-REMY coRPoRArIoN,

or DAYTON, OHIO, A CORPORATION or DELAWARE IGNITION AIPIARATUSApplication filed August 5, 1927. Serial No. 210,822.

This invention relates to ignition apparatus for internal Combustionengines. I

One of its objects is to provide for the con: trol of ignition timing inresponse to englne operating'conditions, so that a timing of theignition will be advanced as the engine speed increases and will beretarded as the engine load increases and vice versa.

A, further object is to provide an ignition timer and distributor unitincluding. a centrifugal device for controlling the angular relation ofthe timer cam to the drive shaft and also a device responsive to enginesuctionfor controlling this relation, each device being operableindependently and capable of operating cumulatively to control thetuning of ignition.

Further objects and advantages of the present invention will be apparentfrom the the accompan following description, reference being had to ingdrawings, wherein a preferred form o embodiment of the present inventionis clearly shown.

In the drawings:

Fig. 1 includes a longitudinal sectional view of an ignition timingapparatus embodying the present invention and a diagram ona smallerscale showing the manner of connecting the suction control with anengine intake fuel passage.

Fig. 2 is a plan view on the line 2-2 of- .Fig. 1, the timer housing anddistributor being removed.

Fig. 3 is a plan view ofthe timer with the distributor rotor and headremoved. Figs. 2 and 3 are drawn to a smaller scale than Fig. 1. y

In the drawing, 20 designates a cup-shaped housing having a bearing 21for supporting a drive shaft 22 having a helically-splined portion 23and a smooth portion of smaller diameter 24. The splined portion 23 isthreadedly engaged by nut 25 drivingly connected with a dished plate 26having a flange 27. The flange 27 supports studs 28 each providing apivot for a weight 29. Each weight 29'com-prises a plurality oflaininations 30 secured by rivets 31, one of which extends through aslot32 in the flange 27. This rivet 31 is provided with an extension 33 forreceiving one end of a spring 34 attached at its other end to anextension '35 of oneof the studs 28 as shown in Fig. 1'. The spring 34yieldingly urges the weights 29 toward the axis of the shaft 22. Eachweight includes a notched portion 36 for receiving a finger 37 extendingfrom. a shaft 38 having a central bore 39 for receiving the smoothportion 24 of the shaft 22.

The shaft 38 has a portion of smaller diameter 4O journalled in a ballbearing 41 which is supported by a timer cup 42. The cup 42 insulatinglysupports a breaker plate 43 having an upright car 44 for supporting anadjustable screw 45 carrying a contact 46. The contact 46 is engaged bya contact 47 carried by lever 48 pivoted at 49. The lever 48 carries aroller 50 for following the cam 51 attached to the shaft 40. A spring 52hearing against the timer cup 42 and connected by a pin 53 with thelever 48 urges the lever toward the cam and also provides a groundconnection between the contact 47 and the timer housing. The cam 51drives a distributor rotor 54 cooperating in the usual manner ignitionas the engine load increases or as the suction of the carburetorincreases, comprisesa device which changes the angular relatlon betweenthe nut 25 and the shaft 22 by moving the nut up and down alonghelicallysplined portion 23' of the shaft. This device thereforecomprises a plate 60 which has a central aperture'for receiving the nut25 and which fits loosely in an annular groove 61 between the nut 25 andthe bottom of the cupshaped plate=26. The plate 60 is attached to anouter metal bellows 62 and an inner metal bellows 63 which in turn areattached to a bottom. plate 64 supported by the bottom of the housing20. The space between the bellows 62 and 63 provides asuction chamber 65which is connected by the pipes 66 and 67 and passage 68 in thecarburetor 69 with a fuel intake pasage 7 O of the carburetor. As 5 theengine load increases requiring the openingofthe carburetor throttle 71,the suction in the carburetor passage 70 willincrease and likewise thesuction in the chamber 65. Therefore the plate 60 and nut willbe 14fmoved downwardly to cause the nut and parts driven thereby including thewe1ghts 2? to be moved in a counterclockwise directlon as -viewed inFig. 2. Therefore the timing of the spark will be retarded with increase1n suction in the'carburetor due to increasing engine load. 7 As theengine load decreases and the throttle 71 is moved nearer to closedposit on to govern the engine, the suction in the earburetor anterior tothe throttle will decrease, thereby permitting the bellows to move theplate 60 upwardly due to their own reslhency. This action will cause therotation of the weights relative to the shaft 22 to be clock- 5 wise asviewed inFigs. 2 and 3, in order to advance the spark as the loaddecreases:

It will be noted that each device controlling the timing of ignition mayoperate independent-1y of the other. The angular movement.

of the nut 25 relative to the shaft 22 does not affect the amountpfangular movement of the cam 51 relative to the nut 25. For example, ifboth speed and load increase, the centrif: ugal device could operate toadvance the spark while the suction responsive device could operate toretard the spark. If the speed be increased as the load decreases, bothdevices will operate to advance the spark, and the total amount ofadvance will be the sum of amounts of advance effected by each deviceseparately.

, Thus both control devices operate independently in order to effect ajoint control of the spark timing. 1

While the form of embodiment of the present invention as'hereindisclosed, constitutes a preferred form, it is to be understood thatother forms might be adopted, all coming within the scope of the'claimswhich follow.

What is claimed is as follows:

- 1. Ignition apparatus'com breaker operatedjby a rotata 1e cam, a driveshaft, an intermediate drive'element through which rotationistransmitted from theshaft member to the cam member, means comprisingan annular expansion chamber responsive to engine loadconditions forvaryin the angular relation between the interme 'ate element and one ofthe members, and means responsive to engine speed for varying theangular relation between the intermediate element and the other of saidmembers.

- breaker operate shaft having a he 'cally splined portion, a

rising a circuit nut movable axially along said splined portion, speedresponsive means for connecting the nut with the cam, while permittingthe nut to move axially and to turn relative to the shaft, and meansresponsive to engine load conditions for moving said nut.

3. Ignition apparatus comprising a circuit breaker operated by arotatable cam, a drive shaft having a helically splined portion, a nutmovable axially along said splined por- 75 tion, means forv connectingthe nut with the cam, while permitting the nut to move axially and toturn relative to the shaft, and means responsive to engine loadconditions for moving said nut. T w

4. Ignition apparatus for internal combustion engines comprising, incombination, an interrupter, a cam for operating theinterrupter, a driveshaft, a member movable axially along the shaft, means for connectingthe member with the shaft so as to turn the member relative to the shaftas it moves along the shaft, means responsive to engine intake suctionfor moving said member and including an annular displacement chambersubstantiallycoaxial with the drive shaft and havinga movable wallconnected with said axially movable member, said means being responsiveto variations in engine load-conditions for moving'said member, andmeans responsive to variations in engine speed for connectingsaidmemberand cam and forchanging the angular relation between them.

5. Ignition apparatus according to claim 4 in which the speed responsivemeans are 1 supported directly by the axially -movable memberand aremovable therewith.

6. Ignition apparatus according to claim 4 in which the axially movablemember is a nut threadedly connected with the drive shaft.

7 Ignition apparatus for internal combustion-engines comprising, incombination, an

interrupter, a cam for operating the interrupter, a drive shaft, amember mo vable alon the shaft, means connecting the member an cam,means for connecting the member and shaft and for causing the member torotate relative to the shaft as it moves along the shaft, and meansresponsive to variations in 1 pressure in the engine intakefor movingthe member, and including" as uction chamber provided by two spacedconcentri metal belows and an annular disc to whiclt' the ends of thebellows are fixed anduto which the 1 2 v axially movable member is*connected.

8. Ignition apparatus for internal combustion' engines comprising, incombination, an r interrupter, a cam for operating the interrupter, adrive shaft, anintermediate drivemembersurrounding the drive shaft andsupported thereby for rotation relative thereto, 2. Ignitionaplparatuscomprising a circuit i b a rotata 1e cam, a. drive a cam-carrying shaftsurrounding the drive shaft and supported thereby for-'rotationrelativethereto, means responsive to variations in engine intake suction forconnecting the intermediate drive-member with one of the shafts and forchanging the angular relation between them, and other means forconnecting the intermediate drive-member with the other of said shaftsand for changing the angular relation between them.

9. Ignition apparatus for internal combustion engines comprising, incombination, an interrupter, a cam for operating the interrupter, adrive shaft, an intermediate drive member surrounding the drive shaftand supported thereby for rotation relative thereto, a cam-carryingshaft surrounding the drive shaft and supported thereby for rotationrelative thereto, means responsive to variations in engine intakesuction for connecting the intermediate drive-member with one of theshafts and for changing the angular relation between them, and meansresponsive to variations in speed for connecting the intermediatedrive-member with the other of said shaftsand for changing the angularrelation between them.

10. Ignition apparatus comprising a circuit breaker operated by arotatable cam, a drive shaft, an intermediate drive element throughwhich rotation is transmitted from the shaft member to the cam member,means comprising an annular expansion chamber responsive to engine loadconditions for varying the angular relation between the intermediateelement and one of the members,'and means movable axially of said shaftand responsive to engine speed for varying the angular relation betweenthe intermediate element and the other of said members.

In testimony whereof I hereto affix my signature.

WILLIAM A. CHRYST.

